Interesting your brothers experience with the Gator. My cousin just bought the Kubota diesel version instead of the Gator. He thought it was more of a work UTV as well.
I really like the "look" of the Gator comparing the two. I've never sat in either.
My brother's and I purchased a 825i as soon as they came out. We use ours at our Cabin in Southern Ohio. Apparently, we should be testers for Deere, as we've had the distinction of being the first in the country to break various components. I will say we really push it to its limits, running up very steep hills that are creek beds or skidder trails with heavy loads. So, we've broken every CV joint, gone through a few tires, and fractured a few parts underneath (dealing with lots of large sharp rocks). Since ours came out, JD improved on the CV joint protection gear and some other things.
Other than it running hot alot, the thing has been fantastic. It is great for getting hunting gear, etc up into the mountain, as well as people. Give's a great ride, and runs places that we've end over ended 4 wheelers. Most of what broke is b/c we really push the thing. But our place has always done that to vehicles. My brother had to order a new fly wheel for a jeep about 20 years ago and was told they don't break... but we broke his, along with 2 other jeeps, 3 pickups, an Explorer, a Cherokee, a few sedans, 3 four wheelers, a JD 625 and a host of other things. But, big sharp rocks, steep terrain, and all that goes with skidder trails makes for a mix that is tough on vehicles.